US2621678A - Drive coupling - Google Patents

Description

Dec. 16, 1952 J. R. sNYDER ETAL 2,621,678

' DRIVE COUPLING y Filed Deo. 21, 1945 2 SHEETS- SHEET 2 Z5 f/ Y W jzL/Enr Jcab Pas .Saya/ee Patented Dec. 16, 1952 UNITED STATES l?AT "liN-T.l OFFICE DRIVE COUBIJNG,

Jacob Rush. Snyder, Cleveland; andiv Frederick AtwoodPea-se, Jr., ClevelandfHeights, Ohio, las signors' tok Thompson ProductsiInC-f, Cleveland; Ohio, la: corporation of Ohio).

Application December 21, l9i4v5, SerialjNo. 636,430

svGllams. 11

This invention relates toa couplingy deviceY for rotatingshaft-like members and particularly to a coupling device normallyv connecting al driving member with a rotatable driven' member; which is arranged to permit expeditious manual rotation ofthe driven. member independently of the driving-member;

In many motor driven devices, and particularly Where the driving mechanismincludesy a gear reduction it is often desired to rotate the driven member manually, particularly when failure oi?l the driving mechanism occurs. When no quick-disconnecting coupling device is provided between the driving and driven members, such manual rotation requires an excessive force especially when manually rotating the driven member directly, due to the large gear ratios generally involved. In still other cases, it is frequently desired to manually. adjust the angular relationship of the driven member relative to the driving` member for somepurpose,= and then recouple the driven member to the driving member in the identical angular relationship as existed prior to the uncoupling of such members. This latter operation is ofV particular utility in the operation of motor driven valves wherein apxed angular relationship must be maintained between the motor and, the, operating shaft ofthe valve, yet it is often desirable to manually operate the valve independently of the motor.

According to one embodiment oi this invention, a coupling plate kis ailxed to the driven member for corotation while a second coupling plate is slidably mounted on thel shaft of a driving member but is rotatable with such driving member. Such driven member may compr-ise the operating post of a valve andthe driving-member the output shaft of a motor driven speed reducing unit. A spring is provided urging the secondV coupling plate axially relative to the driving member andinto abutting or adjacent relationship with the first coupling plate secured; t0 the driven member. Orne or more axially extending peripheral recesses are. provided in., One of the coupling plates and a corresponding number of axially parallel projecting lugs, are provided on the other coupling plate, located so asto engage in the recesses of the other coupling plate in the adjacent coupled position ofv such coupling plates. While not limited thereto, the spacing of the recesses and cooperating lugs is preferably non-uniform about the periphery of the c ouplingl plates, thereby insuring that such plates wm be secured together in only one predetermined angular relationship.

the driven member is provided with any suitabletype` ofwtoolY engaging surfacesuch, for example, as a plurality of opposed flat surfaces which mayl be. conveniently engaged by a wrench-.like tool. Anexternal flange 4is provided on each of the coupling plates and such flanges are located so as to lie on each` side of the toolV engaging surfaces. The spacing between such flanges is proportioned. relative to.- the extent of engagement of the projecting lugs in the recesses sov that the insertion of a wrench between such anges will displace. the two coupling plates relative to each other. a sufficient axial distance to disengage the. projecting lugs from the recesses, thereby disconnecting the driven member from the driving member. After insertion ofthe wrench between the anges of; the coupling plates, the wrench may be engaged on` the tool-receiving surfaces and the driven member rotated by such wrench.

In accordance with a further embodiment of this; invention, similar coupling plates as heretofore describedv are provided respectively on` the driving and'4 drivenv members. The coupling plate mounted on the driving member is axially. movable relative thereto and is spring-biased into abutting relationship with the couplingplate on thedriven member. A projecting'.A lug.- none of such coupling plates` cooperatesA with a recess in the other plate to secure theud-riving and driven members together for rotation in the direction of the driving member.` I-Iowever, onewall of therecess and the corresponding edge of the lug are shaped to *form cooperatingcam surfaces which, when the driven 'memberisV rotated relatively aheadA of the drivingmember, produces an axial displacement of one coupling plate relative to the other sufiicient to disengage the lug from the cooperatingrecess and thus uncouple the driving and driven members. To accomplish the rotation of therdriven member relative` tol the driving member, a ratchet` is formed on theY driven member and this ratchet has a peripheral groove; formed thereon which biiurcates allfof-the teethr ofthe ratghet. A cord-like mmberis then mounted in at least a' Yportion ofsuch peripheral groove and a pawl is secured to the cord. Thus manual pulling of the cord engages the pawl with the teeth of the ratchet and effects rotation of the ratchet, hence rotation of the driven member ahead of the driving member, thereby effecting uncoupling of the coupling plates. The other end of the cord on which the pawl is secured is fastened to a spring-biased reel which, when the cord is manually released, winds up the cord restoring the pawl to an inoperative positive relative to the ratchet.

In the specific application of the second modification of this invention to a motor driven valve, a stop may be provided which is engageable by the pawl as the cord is pulled, thereby limiting the angular movement of the valve post to an amount coincident with the angular separation of two distinct operating positions of such valve post.

Accordingly, it is an object of this invention to provide an improved quick-disconnecting coupling device for shaft-like rotating members characterized by its ease and reliability of operation and simplicity of construction.

A further object of this invention is to provide a quick-disconnecting coupling device for rotating shaft-like members which permits such members to be expeditiously manually uncoupled and then recoupled in identical angular relationship.

One particular object of this invention is to provide a quick-disconnecting coupling device between rotatable driving and driven members wherein the application of a wrench to the driven member to manually rotate such member automatically effects uncoupling of such member from the driving member.

Another particular object of this invention is to provide a quick-disconnecting coupling device between rotatable driving and driven members wherein the manual pulling of a cord-like member eifects uncoupling of the driving and driven members and rotates the driven member independently of the driving member.

A further object of this invention is to provide an improved pawl and detent device for rotating a rotatable body by pulling of a cordlike member.

A specic object of this invention is to provide a drive coupling between a motor driven speed reducing device and the operating post of a rotatable valve member, wherein the drive coupling permits expeditious manual uncoupling of the operating post and rotation of the operating post manually and independently of the speed reducing device, and further such drive coupling permits recoup-ling of the operating post only in the same angular relationship to the speed reducing device as existed prior to uncoupling.

Other and further objects of the invention will be apparent to those skilled in the art from the following detailed description of the annexed sheets of drawings which by way of preferred examples only illustrate two embodiments of the invention.

On the drawings:

Figure 1 is an elevational view, partly in section, of a valve, a motor driven speed reducing device and drive coupling in assembled relation;

Figur 2 is a side elevational View of Figure 1, partly in section and with the operating wrench indicated in phantom;

Figure 3 is an enlarged partial sectional view of Figure 1, taken on the plane III--III thereof and showing the elements of the coupling device in their coupled positions;

Figure 4 is a View similar to Figure 3 but showing a wrench in engagement with elements of the coupling device and such elements in their uncoupled positions;

Figure 5 is an enlarged view of the end face of one of the coupling plates, with other associated parts deleted for clarity;

Figure 6 is a View similar to Figure 1 but incorporating a modication of the drive coupling;

Figure 7 is a side elevational view of Figure 6 having portions thereof cut away for clarity; and

Figure 8 is an enlarged elevational View of the drive coupling utilized in Figure 6.

Referring to Figures l through 5 of the drawings, there is shown a driving member or shaft 2 coaxially disposed in adjacent relationship to a driven member or shaft 6. By way of example, the driving member 2 may comprise the output shaft of an electric motor driven speed reducing unit (not shown) disposed within the housing 3, while the driven member 4 may comprise the operating post of a rotatable valve plug 5 disposed within a Valve housing '1.

A conventional wiring receptacle il may be provided on housing 3 to receive the electric cables (not shown). Motor housing 3 is convenently secured to valve housing 7 by a plurality of screws 2l threadably connecting spaced lugs 23 integrally formed on motor housing 3 with correspondingly spaced upstanding lugs 25 integrally formed on a spacer plate 2l which is in turn secured to valve housing 'l' by suitable screws 39.

Valve housing 'l comprises a hollow casing defining a cylindrical chamber i3 to accommodate rotatable valve member 5 and further defines two or more ports l1 communicating with chamber i3 and which are generally radially disposed relative to the operating post The rotatable valve element 5 is integrally formed with operating post 4 and comprises a -cylindrical member arranged to rotate within chamber i3 of the valve housing 1. To interconnect the ports I1, a hole 29 is provided through rotatable valve element 5 transverse to the axis thereof. Hence, the relative angular position of rotatable valve element 5 with respect to ports I7 determines whether such ports are interconnected or shut olf.

A flange 3| surrounding operating post i journals one end of valve element 5 while the other end is suitably journaled in an end plate 33 which is secured to valve housing 'l by suitable screws (not shown). Suitable gaskets il are provided in cooperative relation between valve housing 'I and rotatable valve element 5 to prevent fluid leakage.

The end of driving shaft 2 is provided with longitudinal splines 6 and on lthis splined end a coupling plate 8 having a splined bore I0 is slidably mounted for axial movement relative to driving shaft 2.

A coupling plate I4 is affixed on the end of the driven shaft or operating post l. A plurality of lugs i6 are provided on the end face l5 of coupling plate I4 projecting in an axially parallel direction toward the end face 9 of coupling plate B. A plurality of recesses i8 are provided in the face of coupling plate 8, and such recesses are spaced and shaped to respectively receive the lugs I6 in engagement therein. A Spring E2, operating between a washer 22a on shoulder 2G on driving shaft 2 and a washer 22 on flange 30 on coupling plate 8, biases coupling plate 3 to- 7 for example, between a fully opened and a fully closed position. g v

Upon release of pulling force applied to the free end of the cord 52, the reel 54 returns the pawl 58 to an inoperative position relative to the ratchet 46 against stop lug 65 rigidly secured to spacer plate 21, winding the cord 52 on itself under the bias of spring 56. y

To return the driving and driven members to their coupled state, the ratchet 45 isA successively advanced by pulling and releasing thecord 52 until vthe lug 34 is aligned with recess 36. Thereupon, the coupling-plate 8 automatically moves axially into coupled relationship with coupling plate I4 under the bias of spring I2. Thus the drive motor and rotatable valve element are recoupled in identical angular relationship that existed prior to luncouplingl This relationship may also be brought about bythe electrical rotation of the coupling plate 8.

In both of the described modifications it should be noted that the drive coupling is located in the space between the speed reducing unit housing 3 and the valve housing '1. Such space is of course provided by the spacer plate 21 and the .radially disposed openings 64 between lthe upstanding lugs 25 on the spacer plate permit convenient manual access to the elements of the drive coupling.

-From the foregoing description, it is apparent that this invention provides a simple and inexpensive quick-disconnecting coupling device for rotatable shaft-like members. Such coupling device is particularly susceptible to manual operation and permits uncoupling to be accomplished by few and simple manual movementsisimultaneouslyl the angular relationship of the driven member may be changed relative to the driving member.

kIt will, of course, be understood that various details of construction may be varied through a wide range without departing from the principles of this invention, and it is, therefore, not the purpose to limit the patent granted hereon otherwise than necessitated by the scope of the appended claims. y

We claim as our invention: l. 4In combination, a rotatable driving member, a rotatable driven member, a rst coupling vplate rotatable with said driving member, a second coupling plate rotatable with said driven member,

at least one of said coupling plates being axially movable relative to its respective rotatable member, resilient means urging said coupling plates axially into coupled relationship, one of said coupling plates having a recess in the coupling face thereof, said other of said coupling plates having a projecting lug engageable in said recess in the coupled position of said coupling plates, cooperatingfaxially inclined cam surfaces on one wall of said recess and one ledge of said lug respectively, said earn surfaces being engageable upon relative rotation of said driven member ahead of said driving member, means for producing relative rotation of said driven member ahead of said riving member, whereby said cam surfaces produce an axial displacement of said coupling plates sunicient to withdraw said lug from said recess, and spring-urged means for restoring said last mentioned means to an inoperative position.

2. In combination, a rotatable driving member,

a rotatablev driven member, a first coupling plate rotatable with said driving member, a second coupling plate rotatable with said driven member, at least one of said coupling plates being axially movable relative to its respective rotatable member, resilient means urging said coupling plates axially into coupled relationship, one of said coupling plates having a recess in the coupling face thereof, said other of said coupling plates having a projecting lug engageable in said recess in the coupled position of said coupling plates, cooperatingV axially inclined cam surfaces on one wall of said recess and one edge of said lug respectively, said cam surfaces being engageable upon relative rotation of said driven member ahead of said drivingmember, a ratchet secured to said driven member in coaxial relation, a manually movable pawl engageable with said ratchet to rotate said driven member relatively ahead of saiddriving member, whereby said cam surfaces produce an axial displacement of said coupling plates sumcient to withdraw said lug from said recess, and spring-urged means for restoring said pawl to an inoperative position relative to said ratchet.

. 3. In combination, a rotatable driving member, arotatable driven member, a first coupling plate rotatable with said driving member, a second coupling plate rotatable with said driven member, at least one of said coupling plates being axially movable relative to its respective rotatable member, 'resilient means urging said coupling plates axially into coupled relationship, one of said coupling plates having a recess in the coupling face thereof, said other of said coupling plates having a projecting lug engageable in said recess in the coupled position of said coupling plate, cooperatingaxially inclined cam surfaces on one wall of said recess and one edge of saidlug respectively, said cam surfaces being engageable upon relative rotation of said driven member ahead of said driving member, a ratchet secured to said driven member in coaxial relation and having a peripheral groove thereon, a cord-like member having a portion thereof engageable in said groove, a pawl secured to said cord-like member and arranged whereby pulling of said cord-like member engages said pawl with said ratchet to rotate said driven member relatively ahead of the driving member, whereby said cam surfaces produce an axial displacement of said -coupling plates sufficient to withdraw said lug from said recess, and a spring-actuated reel engaging said cordlike member to restore said pawl to an inoperative position relative to said ratchet.

4'. AIn combination, a rotatable driving member, a rotatable driven member, a rst coupling plate rotatable with said driving member, a second coupling plate rotatable with said driven member, at least one of said coupling plates being axially movable relative to its respective rotatable member, resilient means urging said coupling plates axially into coupled relationship, one of said coupling plates having a recess in the coupling face thereof, said other of said coupling plates having a projecting lug engageable in said recess in the coupled position of said coupling plate, cooperating axially inclined cam surfaces on one wall of said recess and one edge of said lug respectively, said cam surfaces being engageable upon relative rotation of said driven member ahead of said driving member, a ratchet secured to said driven member in coaxial relation and having a peripheral groove thereon, a cordlike member having a portion thereof engageable in said groove, a pawl secured to said cord-like member and arranged whereby pulling of said cord-like member engages said pawl with said ratchet to rotate said driven member relatively ahead of the driving member, whereby said cam 5. ward abutting or adjacentv relationship'with couplin'g plate' I4 in` which posit-ionthe lugs I6 are engagedY in the recessesV I8. Thus the coupling platesare coupled together for rotation and hence the driving and driven members are connected forno-rotation.

It will be obvious to one skilled in the art that thernountingarrangement of the coupling plates 8j and I4y could be reversed without detriment to their' operation, i. e., the coupling plate 8 could bsecur'ed'Whilethe-coupling plate I4 is axially movable.

Thespacing of the lugs I6 and the recesses I8 about the axis of their respective coupling plates is shown in Figure 5 as non-uniform. Suchnonuniform spacing insures that the driving and driven members will always be connected together in identical angular relationship. In the event that it is desired to index the driven member relative to the driving member through a` plurality of successive equal angular increments, then the spacing of the lugs I6 and recesses I8 should be uniform and angularly separated by the amount-of the desired angularv indexing.

The coupling plate I4, which is secured to the drivenY member 4, has formed on its periphery, adjacentits end face I5, tool-receivingr surfaces 24,- which may comprise opposed flat surfaces suitably spaced about the periphery of coupling plate I4' to permit such surfaces to be readily engaged by the jaws 28 of a wrench-type tool 26.

A flange 30 is providedY adjacent the end face 9of coupling plate 8 and likewise a liange 32 is provided on coupling plate I4 adjacent the inside end' of the tool-receiving surfaces 24. The separation of the flanges 30 and 32 in the ycoupled position -of the coupling plates is preferably proportioned to be substantially less than the width of the jaws 28 of the -tool 26, and valso proportioned relative to the extent of engagement of thelugs I6 in the recesses I8 so that upon the insertion of the jaws 28 of tool 26 between the anges 30 and 32, as illustrated in Figure 4,- the lugs I6 will `be completely withdrawn from the recesses I8 and thus the driven member uncoupled from the driving member. The insertion of the tooljaws 28 between the flanges 30 and 32, of course, produces an axial movement of coupling plate 8 awayfrom coupling plate I4v which is resisted by the bias of spring I2.

The driven member may then be conveniently rotated manually by the wrench or tool 26 operating. on surfaces 24 and it should be'noted that such rotation can be accomplished with'very little effort since' the driving member and its usually connected gear train are completely separated from the driven member. When it is desired to restorel theA driving and driven members to their coupled relationship, it is merely necessary to rotate the-driven member to the position Where the lugs I6 align with the recesses I8. rThere-V after, the removal of the tool 26from between the nang'es 30 and 32 will immediately permit the coupling! plates 8 to move axially' towardlplate I4 under" theA force of spring I2V to return to' the coupled relationshipy as soon as the lugs and-recessesare aligned. The lugs and recesses may also be' realigned by electrical rotation of the driving member' 2 andcoupling plate'` 8'.

The non-uniformspacing of the lugs I6 and the recesses I8 insures thatV the driving and driven members are recoupled in the identical angular relationship as existed prior to uncoupling. This feature is ofA particular advantage in the operation of motordriven valves for, as is: commonly known; the control circuit (not showm for the' driving motor operates properly only Whenanxed angularrelationshi'p exists between the rotatable valve element and the driving' motor. Hence,l a` drive coupling in accordance with thisinvention prevents manual operation of theI valve from interfering with subsequent remotely controlledI motor driven operation;

I`n` the"` fnodificaticmvv disclosed in 'igu'res' 6 through 8, wherein identical 'numerals refer to parts similar to those describedin connection with Figures 1e5, the driving inember or shaft- Zand thel driven member or operating post 4 are again provided with coupling plates 8ly and I4,V respectively.- Coupling plate1f8 is slidably' mounted upon the splined end 6* of the driving shaft' 2" andis biasedin'to abutting or-adj ac'ent `relatienship-with coupling plate I4 by spring I2. Coupling plate I4 is aga-in providedl with one o r a plurality of axially parallel projecting' lugs. 34; while coupling plate 8f is provided with corresponding recesses 36 to receivesuch lugs in the coupled position of the coupling'plates.

In this modification, one wall 31 of` recess 36 and the corresponding edge 35 of the lug 34- are disposed in general radial relationship with respect to the axis of the driving member. Hence, the driving membery will drive the driven member in one direction. The opposite wall 42 ofthe recess 36 and the opposite edge 44 of the lug 34 are, however, axially inclined and shaped to provide cooperating cam surfaces which, when the driven member is rotated relative to the driving member in the same direction, or in other words, ahead of the driving member, will produce a camming action between the coupling plates 8 and I4, moving coupling plate 8 axially away from coupling plate I4 against the bias of spring I2. Thus, the driving and driven members may be readily uncoupled when the driving member is at rest by manual rotation of the driven member ahead of the driving member, or conversely, by rotating the driving member relative to the driven member in a reverse direction.

To accomplish the uncoupling relative rotation of the driving and driven members, a ratchet 46 is formed on the periphery of coupling plate I4. Such ratchet is provided with a plurality of peripherally spaced teeth 48 and a peripheral groove 50 is provided therein which bifurcates all of the teeth 48. For convenient manual rotation of the ratchet 46, a cord 52 is utilized which at least partially surrounds the ratchet46, lying in the groove 50. One end of the cord 52 is secured by torsion spring 56 in a direction tending to Wind the cord 52 thereon. v

Intermediate the reel 54 and the ratchet 46, a pawl 58 is rigidly secured to the cord 52. The forward face 6U of the pawl 58 is suitably shaped to engage the teeth 48 of the ratchet 46. Thus, upon manually or otherwise pulling of the free end of cord 52, the pawl 58 will be advanced into engagement with the teeth 48 of ratchet 46 and the ratchet rotated. Hence, the driven member is conveniently manually rotated.

If desired, a stop 62 may be xedly secured to the spacer plate 21 in the path of movement of the pawl 58 as it rotates the ratchet 46. The stop 62 thus insures that the driven member may be successively advanced by only a predetermined increment. The extent ofr rotation permitted by stop 62 may conveniently be selected to permit operation of rotatable valve element between two successive angularly displaced operative positions,

surfaces produce an axial displacement of said coupling plates sufficient to withdraw said lug from said recess, a fixed stop member disposed in the rotative path of said pawl to limit the rotation producing movement of each actuation of said pawl, and spring urged means engageable with said cord-like member to return said pawl to an inoperative position relative to said ratchet upon release of pulling force on said cord-like member.

5. In combination, a driving member, a rotatable driven member, a one-way coupling device constructed and arranged to secure said driven member to said driving member in predetermined angular relationship for one direction of rotation of said driven member and to disconnect said driven member from said driving member for independent rotation by relative rotation or said driven member ahead of said driving member, a ratchet secured to said driven member in coaxial relation, and a manually movable pawl engageable with said ratchet to rotate said driven member ahead ci said driving member, whereby actuation of said pawl uncouples said driven member and rotates said driven member a relative to said driving member.

6. In combination, a driving member, a rotatable driven member, a one-way coupling device constructed and arranged to secure said driven member to said driving member for one direction of rotation of said driven member and to disconnect said driven member from said driving member by relative rotation of said driven member ahead of said driving member, a ratchet secured to said driven member in coaxial relation, said ratchet having a peripheral groove thereon, a cord-like member having a portion thereof engageable in said groove, a pawl secured to said cord and arranged whereby pulling of said cord engages said pawl with said ratchet to rotate said driven member ahead of said driving member, and a spring-actuated reel engaging said cord-like member to restore said pawl to an inoperative position relative to said ratchet.

7. in an electric motor driven valve apparatus of the type including an electric motor and a rotatable valve plug in a ported casing driven by the motor to various port controlling positions, the improvements of a splined drive shaft adapted to be rotated in coaxial disposition with a driven memben'a irst coupler adapted to be siidably splined on the drive shaft, a second coupler, a spring urging said first coupler axially into a coupled position relative to said second coupler, said couplers having interfitting drive connections thereon engageable in said coupled position, cam means for moving said first coupler axially out of coupled relationship with said second coupler upon relative rotation of said second coupler ahead of said rst coupler, and manually operable means for rotating said second coupler ahead of said first coupler including a ratchet having a driving connection with said second coupler and having a peripheral groove thereon, a cord-like member having a portion thereof engageable in said groove, a pawl secured to said cord-like member and arranged whereby pulling of said cord-like member engages said pawl with said ratchet to rotate said second coupler in increments corresponding to an angular spacing pattern, and a spring actuated reel engaging said cord-like member to restore said pawl to an inoperative position relative to said ratchet.

8. 1n an electric motor driven valve apparatus of the type including an electric motor and a rotatable valve plug in a ported casing driven by the motor to various port controlling positions, the improvements of a splined drive shaft, a rst coupler adapted to be slidably splined on the drive shaft, a second coupler, a spring urging said iirst coupler axially into a coupled position relative to said second coupler, said couplers having intertting drive connections thereon engageable in said coupled position, cam means for moving said rlrst coupler axially out of coupled relationship with said second coupler upon relative rotation of said second coupler ahead of said first coupler, and manually operable means for rotating said second coupler ahead of said rst coupler including a ratchet having a driving connection with said second coupler in coaxial relation and having a peripheral groove thereon, a cord-like member having a portion thereof engageable in said groove, a pawl secured to said cord-like member and arranged whereby pulling of said cord-like member engages said pawl with said ratchet to rotate the second coupler, and a stop member disposed in the rotative path of said pawl about said ratchet, said stop member being located in predetermined relationship relative to the pawl to limit the rotation of said second coupler.

JACOB RUSH SNYDER. FREDERICK ATWOOD PEASE, J a.

REFERENCES CTED The following references are of record in the iile of this patent:

UNITED STATES PATENTS Number Name Date 284,475 Perkins Sept. 4, 1883 577,490 McGuire et al Feb. 23, 1897 801,012 Howard Oct. 3, 1905 937,127 West Oct. 19, 1909 980,502 Dunkel Jan. 3, 1911 1,193,008 Fuller Aug. 1, 1916 1,405,001 Reichelt Jan. 3l, 1922 1,409,103 Hawthorne Mar. 7, 1922 1,462,879 Woodward July 24, 1923 1,502,915 Neuwerk July 29, 1924 1,953,132 Lyon Apr. 3, 1934 2,203,233 Panish June 4, 1940 2,390,882 Hopkins Dec. 11, 1945 FOREIGN PATENTS Number Country Date 24,297 Great Britain of 1915 83,384 Austria of 1921 154,063 Switzerland of 1932 334,778 Great Britain Sept. 11, 1930 411,370 Great Britain of 1934

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